Built to Run

A new study came out this month which concluded (in rats, which usually translates well to humans) that long distance running versus strength training and high intensity training) proved to be the best for our brains. They based this on looking at what happened to the brain after it experienced the 3 different forms of training. What they discovered in the rats is that the long distance running produced much greater “neurogenesis” than the other 2 forms. Second place was high intensity training followed by strength training. Actually, according to the study, the resistance-trained rats’ production of neurogenesis was not much better than a couch potato, although these rats were quite a bit stronger at the end of the study.

Again, this study was done with rats and doesn’t in any way rule out the benefits of strength training or high intensity training. On the contrary, there are plenty of other studies that have shown the benefits for the body and the brain in other ways, but this particular study looked at neurogenesis of the hippocampus and the production of the substance known as brain-derived neurotrophic factor (BDNF). It is this compound which is largely responsible for the regulation of neurogenesis. According to the research, long distance running seems to lead to the most production of BDNF.

After I read the blog post (link below) which described this study in great detail, I thought really hard about it and realized that this just makes a lot of sense. So I won’t rehash the study here; it is included below for those of you interested. Instead, I want to talk about why, again, maybe we should not be surprised by this study or its results.

Speaking from an evolutionary point of view, we are, in fact, built to run, and are actually built for endurance. When compared to the animal kingdom, we are by far not the strongest, nor the fastest, compared to most creatures on the planet. Physically, we really don’t measure up at all except in a couple of very crucial areas, and it has nothing to do with our big brains; that was actually more of a by-product of what did occur. We, as a species, took an alternative path to become one of the most successful hunters. Instead of becoming stronger and faster and have sharper claws and teeth, etc., our ancestors ended up going in the direction of the tortoise, not the hare. For humans on the plains of Africa, slow and steady proved to win the race in matters of ‘survival of the fittest.’ Unlike other mammals, we became bi-pedal. Not only did this give an advantage in vision by extending our horizon, but it made it better for the dissipation of heat. We also sweat; most mammals do not, they pant. In car terms, we became a water-cooled engine vs an air-cooled one. We know how well Volkswagen did with their air-cooled engines, and this proves true as well for mammals. We evolved to withstand and endure the heat much better than the animals we hunted. We also developed another unique feature. Unlike hoofed animals, our legs were able to develop into springs. Our joints and soft tissue, as in muscles and tendons and ligaments have, when used correctly, a great capacity to store and release elastic energy. This other feature also gave us an extraordinary ability to use less energy than the prey we were chasing. In a head-to-head foot race, we would never be able to catch such prey; they evolved to outrun lions and cheetahs. But if we could keep them in sight and force our prey to to run away from us over and over again during the course of a hot day, we would outlast them; they would literally collapse from heat exhaustion. A possible reason for why our stone tools didn’t change much for thousands of years is likely because they didn’t have to. By the time we got to the collapsed animal, we would have performed nothing more than a simple mercy killing, and then only needed the stone knife to carve the meat.

We actually still see this exact form of hunting today, and it is called “persistence hunting.” This style of hunting has been long held by anthropologists as likely being the oldest form of hunting and what helped give us our big break. So in this, we can start to see the pattern. If nature offers rewards for hard work, then we can now see why the brain would go to so much trouble to reward us for running long distances. This also, then, explains why runners get the “runner’s high,” and why they seem almost cult-ish and certainly obsessive about running so much and running every day – which is now what leads me to my next point.

We are built to run (a certain way), but we still need to consider over-training in modern terms. Even the persistence hunter did not go out again the next day; his buddy would, then the next member of the tribe would take his turn. In fact, it would be days, or even weeks, before that specific hunter would test his metal again. He would be allowed to recover, and this has to be true for our modern jogger as well. Jogging a couple of times a week will still offer great benefit to your brain, while at the same time minimize your risk to overuse and wear and tear injuries.

This brings me to the final point I wish to discuss, and it goes back to our ability, versus our prey, to be able to capitalize on our bodies’ adaptation to be more springy. This only occurs if we do it a certain way. If we don’t, we can actually cause more harm than good, injuries being the biggest culprit. We only get the elastic effect from our legs if we land and strike the ground correctly. Nowadays, it is being referred to as barefoot running and it is starting to gain in popularity, largely because most who turn to it have hurt themselves running incorrectly and have been looking for a way to continue running without the injuries. I won’t get into the whole no-shoe-or-flat-shoe-versus-traditional-shoe debate, but I will say that even if you are wearing the traditional running shoe, you will still want to be sure you are landing on the the ball of your foot and not heal striking. It is heal striking that slows us down, wipes out our capacity to utilize our tissues’ elastic properties, and leads to the injuries which result from the constant pounding. Heal striking also makes it more difficult to have the faster cadence we want in order to maximize the elasticity in our tissues.

Below are the links to both the study and two videos on barefoot running that I found to be really good at explaining and demonstrating the technique, as well as a neat video on persistence hunting.

Some key things I wish to highlight from the videos will be, of course, where you land on your foot; posture; cadence/tempo; and that you will definitely want to allow for an adaptation period. As mentioned in the Terra Plana video, if you run 10km, don’t go and immediately run 10km the new way. Run one km and allow your body to make the appropriate adaptions as it learns the new technique and the right muscles start to strengthen and become more engaged.